Chapter 84The Reflexive yay-

84.1 The reflexive yay- in the valency system

The prefix yay- ‘reflexive’ fills the object position of a transitive verb with a participant coreferential with the subject, reducing arity by one and converting the base transitive to an intransitive Nakagawa (2024: 188); Bugaeva & Kobayashi (2022: §4.2.2). Placed in the first-person plural, a verb bearing yay- takes the intransitive S-suffixes =as (exclusive) or =an (fourth-person) rather than the transitive A-prefixes — the person-affix test of the derivation described in Chapter 73 (Valency, Voice, and Noun Incorporation: Overview) Satō (2008: 96); Nakagawa (2024: 137). A sister prefix si- ‘indirect reflexive’ occupies the same template slot and carries the same arity value; its own distribution and the two prefixes' contrast are treated below and in Chapter 85 (The Reflexive-Possessive si- and the yay-/si- Division).

Nakagawa lists yay- among the 名詞的接頭辞 (nominal prefixes) of the verb-derivation chapter alongside si-, the reciprocal u- ‘reciprocal’, the antipassive i- ‘antipassive’, and the lexical body-region prefixes he- ‘head of’/ho- ‘bottom of’, all of them arity −1 and all filling the object slot from the inside of the verb word Nakagawa (2024: 185–192). Chapter 83 (The Antipassive / Detransitive i-) and Chapter 86 (The Reciprocal u-) develop the parallel operators. Ijäs's learner lessons (L3 and L9) do not cover the reflexive prefixes, as she addresses them in later material Ijäs (2023).

84.2 Morphological range and the possessive yay-

yay- is nearly unrestricted in base selection: it attaches to transitives and ditransitives of any semantic class, and to derived transitives (causativized or applicativized stems) Nakagawa (2024: 188). The prefix also attaches to nominals, where arity is unchanged because a noun carries no object slot to absorb — the reading is then possessive, 'one's own': yay-kotan ‘one's own village’ (yay- + kotan ‘village’) is a representative form Nakagawa (2024: 188).

A productive subtype is the quasi-possessive reflexive Bugaeva & Kobayashi (2022: §4.2.2): where an incorporated body-part noun is interpreted as belonging to the subject, yay- supplies the possessor rather than filling the object slot directly. In yay-par-oyki ‘feed oneself’ (literally 'do about one's own mouth'), par ‘mouth’ is incorporated as the object of oyki ‘do about, handle’, while yay- identifies the subject as the possessor of that mouth. The arity is still reduced by one because the incorporated noun absorbs the object slot; the reflexive element determines whose body part is implicated. This intersects with the object-incorporation system treated in Chapter 88 (Object (Patient) Noun Incorporation).

The accent of yay- is stable: the prefix carries primary stress as yáy- regardless of the following segment, unless lexicalization has displaced it Nakagawa (2024: 188). Forms such as yáyesiru confirm that the accent falls on yáy even before a vowel-initial stem; this accent pattern is corroborated by community corpus observation (nukopoli, aynu-corpora Discord 2024, aynu-corpora Discord (2023–2026)) ‹corpus-confirmed›.

si- is more restricted than yay- in base selection, and when both co-occur the ordering is fixed: yay-si-turi-re 'lay oneself down stretching' places yay- outside si-, while the reverse *si-yay- is unattested Nakagawa (2024: 189). Nakagawa infers that si- sits closer to the root, behaving more like a forming element than an independent prefix.

84.3 Self-affecting verb classes: grooming, emotion, and self-transformation

Three semantic fields attract yay- most productively. Body-treatment and grooming verbs form the first: yay-kara ‘treat oneself, attend to oneself’ builds on kara ‘treat, handle’, the same verb that underlies cise-kar ‘build a house’ and related compounds (see Chapter 60 (Denominal and Deverbal Verb Derivation)). Community corpus work independently documents -kar as productive for 'handle/treat' operations — nimawe-kar (treat with a bark compress), osoro-kar — making yay-kara 'treat oneself' the expected reflexive of that class (nukopoli, aynu-corpora Discord 2024, aynu-corpora Discord (2023–2026)) ‹corpus-suggested›. A rolling-about verb in the Saru narrative corpus shows causative stacking on a grooming-motion base:

A community decomposition of yayhonokka 'educate, discipline' as yay-ho-nok-ka (REFL-bottom.body.region-CAUS) would show yay- stacking over the body-region prefix ho- and a causative suffix, with cross-dialectal support from Saru and Shizunai forms (ku=yayhonokka; ci=honokka; taan hanokka) (nukopoli, aynu-corpora Discord 2026, aynu-corpora Discord (2023–2026)) ‹contested›. The decomposition has not been verified against the analytic literature.

Emotion and mental-state verbs make up a second field. Ainu transitive verbs of feeling take a stimulus as their object; yay- reflexivizes that position, yielding an intransitive of self-directed affect. The minimal pair yay-rayke 'commit suicide' vs si-rayke 'be destroyed by misfortune', both from rayke ‘kill’, shows how the same base divides between the two prefixes; the opposition is examined in the yay-/si- section below Nakagawa (2024: 188–189).

Self-transformation verbs form the third class. With kar ‘make, do’, the prefix yields yay-kar 'transform oneself, take on a different form':

84.4 The yay-/si- distinction: competing analyses

The functional boundary between yay- and si- has produced several accounts that remain in tension Bugaeva & Kobayashi (2022: §4.2.2); Nakagawa (2024: 187–189); Satō (2007). The four most developed positions are set out in the table below; the sources for the first two and third are cited second-hand through the works that survey them.

For the grammar's glossing practice, Bugaeva's 2025 diachronic formulation is the most useful high-level distinction: yay- is REFL proper, while verbal si- has shifted along the common path from reflexive to autocausative and only secondarily to anticausative. The older direct/indirect terminology remains important for explaining individual examples, but it is no longer the primary glossing distinction used in the morpheme database Bugaeva (2025: §3.1.2).

Satō's direct/indirect account, developed for Chitose, is adopted by Nakagawa and the Handbook as the current best analysis ‹contested› Satō (2007); Nakagawa (2024: 189); Bugaeva & Kobayashi (2022: §4.2.2). It holds that yay- marks an action the subject performs directly on itself, without requiring any mediating agent or social condition. si- marks a situation where the subject's involvement is indirect: the outcome is achieved through another participant's action, through circumstances beyond the subject's control, or through a state that holds only because others perceive it as holding.

The canonical Chitose minimal pair is yay-pusu 'pop up by swimming (volitionally)' vs si-pusu 'float of itself (spontaneously)', both from pusu ‘float something up’ Satō (2007). The si- form applies to a physical property of spruce:

The si- class also covers a productive 'pretend' construction: si-mokor-e 'feign sleep', si-kamuy-ne-re 'pretend to be a deity', si-ranpewtek-ka 'pretend to know nothing' Nakagawa (2024: 189); Satō (2007). In each case the subject's performed state depends on how others perceive her — a condition that cannot hold without an audience, hence the indirect marking:

From Nakagawa, a parallel emotional pair: yay-rayke 'commit suicide' (direct, deliberate self-directed action) vs si-rayke 'be destroyed, come to ruin (by misfortune)' (the outcome is brought about by external forces) Nakagawa (2024: 188–189). Bugaeva and Kobayashi add yay-etaye 'draw oneself out (actively)' vs si-etaye 'withdraw, pull oneself back in (in response to something)' Bugaeva & Kobayashi (2022: §4.2.2). The Shizunai corpus supplies an attested instance of si-etaye where the withdrawal is triggered by being seen:

Satō himself notes that the direct/indirect analysis has not reached consensus (定説ではない) Satō (2007); Nakagawa (2024: 189). The earlier intentional/unintentional framing (Kindaichi, Tamura) remains in pedagogical use ‹contested›. A community reformulation characterizes yay- as 'by one's own power' (reflexive) and si- as 'happens to / gets through others' (anticausative), with yaykaopiwki 'save oneself by one's own action' cited as a diagnostic (nukopoli, aynu-corpora Discord 2024, aynu-corpora Discord (2023–2026)) ‹contested›. This formulation is consistent with Satō's account while aligning the si- end with anticausative typology. The hypothesis that the two prefixes represent historically distinct voice categories rather than two subtypes of reflexive (aomidori_cs_, aynu-corpora Discord 2023, aynu-corpora Discord (2023–2026)) ‹speculative› — no diachronic evidence bearing on a pre-reflexive function of either prefix has been identified in the sources consulted for this grammar. Bugaeva and Kobayashi note that no other reported language encodes the distinction between dependence-on-others vs absence-of-such-dependence through a pair of reflexive prefixes, making the Ainu opposition typologically unusual Bugaeva & Kobayashi (2022: §4.2.2).

The full treatment of si- — including its unaccusative uses, its possessive-reflexive function with incorporated body-part nouns (si-etu-uyna 'hold one's own nose'), and the pretend-to constructions — is in Chapter 85 (The Reflexive-Possessive si- and the yay-/si- Division).

84.5 Stacking with applicatives and the verb-word template

yay- combines freely with the applicative prefixes e-, ko-, and o- (see Chapter 78 (The Applicative System: Overview and the Preverb-vs-Applicative Debate)). Since an applicative raises arity by one (+1) and yay- lowers it by one (−1), their combination on a transitive base preserves the original transitivity while shifting which object position holds the reflexive participant. On a base that already has an outer applicative-object, yay- fills the inner original-object slot with 'self'; the outer applicative slot remains available for an external NP.

The combination ko-yay-irayke 'be grateful to someone for something one has experienced oneself' is attested in the Saru narrative corpus — here ko- promotes the deity as the addressee-goal, and yay- fills the inner object of irayke ‘be grateful’ with the subject:

The derivational chain through ruska ‘be angry at’ demonstrates the calculus across further steps: ruska (vt) → ko-ruska (vd, 'be angry toward') → yay-ko-ruska (vt, 'be angry at oneself') → i-ruska (vi, 'be angry', object defocused) — each step changes arity by exactly one unit Nakagawa (2024: 212); Satō (2023: 40) ‹consensus›. The antipassive i- in the same chain is treated in Chapter 83 (The Antipassive / Detransitive i-).

The verb template places reflexive and applicative prefixes inside the person-index layer and outside the root: person-index — reflexive/applicative — root — forming-suffix — causative — person-index Nakagawa (2024: 210–212). Two reflexive prefixes and two applicatives can co-occur on a single root, as in the word a=e-yay-ko-tuyma-si-ram-suy-pa discussed in Chapter 73 (Valency, Voice, and Noun Incorporation: Overview) Shibatani (1990: 73); Bugaeva (2014). A community-proposed decomposition of yaykipniwkes as yay-ki-p-niwkes — with ki 'do' as a light verb and niwkes as the state predicate (nukopoli, aynu-corpora Discord 2024, aynu-corpora Discord (2023–2026)) ‹contested› — illustrates the opaque prefix stacking that occurs in this zone; the analysis awaits verification against primary morphological descriptions. The reciprocal u-, which parallels yay- in its arity value while filling both S and O slots simultaneously, is in Chapter 86 (The Reciprocal u-).